WO2003087941A1 - Positively photosensitive resin composition and method of pattern formation - Google Patents

Abstract

A positively photosensitive resin composition which can be developed with an aqueous tetramethylammonium hydroxide solution having an ordinary concentration, has high sensitivity and excellent resolution, and is excellent in heat resistance, surface smoothness, transparency, etc. and reduced in water absorption; and a method of forming from the composition a pattern having any desired section such as a semicircle or trapezoid. The positively photosensitive resin composition comprises an alkali-soluble resin, a 1,2-quinonediazide compound, a crosslinking compound having two or more epoxy groups, and a surfactant, the alkali-soluble resin being a copolymer comprising essential units derived from a carboxylated acrylic monomer, a hydroxylated acrylic monomer, and an N-substituted maleimide. By changing conditions for the post-baking of this composition, a pattern shape having any desired section such as a semicircle or trapezoid is obtained.

Description

 Description: Positive photosensitive resin composition and pattern forming method

 The present invention relates to a positive photosensitive resin composition. More specifically, interlayer insulating film of thin film transistor (TFT) used for liquid crystal display element (LCD), protective film and flattening film of color fill, unevenness under A1 film used as reflector of reflective display The present invention relates to a positive photosensitive resin composition suitable as a material for forming a film, a microphone lens material, an insulating film of an organic EL element, and the like, and a method for forming a pattern thereof. Background art

 Generally, display materials such as a liquid crystal display element and an organic EL element are provided with an electrode protective film, a flattening film, an insulating film and the like. Acrylic resin, nopolak resin, polyimide resin and the like are used for these materials. When forming these protective films, flattening films, and insulating films, the required pattern shape is formed by using a photolithography method. However, it has been difficult to maintain the heat resistance, transparency, and adhesion of the film obtained after post-baking while maintaining sufficient sensitivity during exposure and development. In general, a photosensitive resin using an alkali-soluble acrylic resin has high transparency and high sensitivity, but has low heat resistance, and has a concentration of 2.38% by weight, which is generally used for developing photoresists. It was difficult to perform development using an aqueous solution of tetramethylammonium hydroxide without dilution.

On the other hand, in general thermosetting photosensitive acrylic resin, the glass transition temperature of the base polymer is low, and reflow occurs before crosslinking, and the pattern shape is limited to a semicircular pattern. In addition, in order to obtain a trapezoidal pattern, it is necessary to increase the cross-linking rate higher than the reflow rate. A trapezoidal pattern can be obtained by crosslinking before reflow by using a polymer obtained by copolymerizing an unsaturated compound containing a oxy group, for example, by increasing the thermal crosslinking property.However, the storage stability of the resin composition is reduced. SUMMARY OF THE INVENTION The present invention, which has a problem such as badness, has been made in view of the above circumstances, and uses an aqueous solution of tetramethylammonium hydroxide having a concentration of 2.38% by weight, which is generally used in a photoresist process. Positive-type photosensitive resin composition that can be developed, has high sensitivity, has excellent photosensitive characteristics with excellent resolution, and has excellent properties such as heat resistance, flatness, transparency, and low water absorption. About. It is still another object of the present invention to provide a positive photosensitive resin composition and a pattern forming method capable of forming a pattern having an arbitrary cross-section of a semicircular or trapezoidal pattern after curing under the conditions of the bast bake. Disclosure of the invention

 As a result of intensive studies to solve the above-described problems, the present inventors have reached the present invention having the following gist.

 1. A composition comprising an alkali-soluble resin, a 1,2-quinonediazide compound, a crosslinkable compound containing two or more epoxy groups, and a surfactant, wherein the alkali-soluble resin is A positive photosensitive resin composition characterized by being a copolymer comprising, as essential components, an acryloxyl group-containing acryl monomer, a hydroxyl group-containing acrylic monomer and an N-substituted maleimide.

 2. With respect to 100 parts by weight of the alkali-soluble resin component, 1,2-quinone diazide is 5 to 100 parts by weight, and a crosslinkable compound containing two or more epoxy groups is 1 to 50 parts by weight. 2. The positive photosensitive resin composition according to 1, wherein the positive photosensitive resin composition contains 0.01 to 2 parts by weight of a surfactant.

 3. The positive photosensitive resin composition according to 1 or 2, wherein the copolymer has a number average molecular weight of 2,000 to 9,000.

4. As a monomer component constituting the above copolymer, it contains a lipoxyl group The positive type according to any one of 1 to 3, comprising 5 to 30 mol% of an acryl monomer, 5 to 50 mol% of a hydroxyl group-containing acryl monomer, and 10 to 70 mol% of an N-substituted maleimide. Photosensitive resin composition.

 5. The positive photosensitive resin composition according to any one of 1 to 4, wherein the surfactant is a fluorine-based surfactant.

 6. A pattern characterized by obtaining a pattern shape having a semicircular or trapezoidal arbitrary cross section by using the positive photosensitive resin composition according to any one of the above 1 to 5 and changing the post-baking conditions. Forming method. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a scanning electron micrograph showing a pattern having a semicircular cross section in Example 1.

 FIG. 2 is a scanning electron micrograph showing a pattern having a trapezoidal cross section in Example 2. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, the photosensitive resin composition of the present invention will be specifically described.

Stiffness soluble resin>

 The alkali-soluble resin contained in the positive-type photosensitive resin composition of the present invention is a copolymer of an acryloxyl group-containing acrylic monomer, a hydroxyl group-containing acrylic monomer and an N-substituted maleimide (hereinafter referred to as an alkali-soluble resin). (Also known as a copolymer).

 The acryloxyl group-containing acryl monomer constituting the alkyd soluble resin copolymer is not particularly limited, and specific examples include acrylic acid and methacrylic acid. These acryloxyl-containing acryloxyl monomers may be used alone or in combination of two or more.

The proportion of the acryloxyl group-containing acrylyl monomer in the copolymer is preferably 5 to 30 mol%, more preferably 5 to 25 mol%, and most preferably 5 to 20 mol%. Contains lipoxyl group 03 04954

4 When the acrylyl monomer content is less than 5 mol%, the copolymer has insufficient solubility in the copolymer, and when it exceeds 30 mol%, the resolution is reduced. When the amount of the acryloxy group-containing acryloxyl monomer is large, the storage stability of the positive photosensitive resin composition of the present invention may be deteriorated.

 The hydroxyl group-containing acrylic monomer constituting the soluble resin copolymer is not particularly limited, but specific examples thereof include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate and the like. These hydroxyl group-containing acrylic monomers may be used alone or in combination of two or more.

 The proportion of the hydroxyl group-containing acrylic monomer in the soluble resin copolymer is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, and most preferably 20 to 30 mol%. . If the amount of the hydroxyl group-containing acrylic monomer is less than 5 mol%, the alkali dissolving resin copolymer will have a high alkali dissolution rate, and it will not be possible to obtain a sufficient process resin. On the other hand, if it exceeds 50 mol%, the water absorption of the cured resin increases. The N-substituted maleimide constituting the copolymer is not particularly limited, and specific examples include cyclohexylmaleimide, phenylmaleimide, methylmaleimide, and ethylmaleimide. Those having no aromatic ring are preferred from the viewpoint of transparency, and xylmaleimide is most preferred from the viewpoint of developability, transparency and heat resistance.

 The ratio of the N-substituted maleimide in the copolymer is preferably 10 to 70 mol%, more preferably 15 to 50 mol%, and most preferably 20 to 40 mol%. It is. When the N-substituted maleimide is less than 10 mol%, the Tg of the alkali-soluble resin copolymer becomes low, making it difficult to obtain a trapezoidal pattern, and the heat resistance of the obtained powder. When the content is more than 0 mol%, it is difficult to control the pattern shape.

Alkyri-soluble resin copolymer is an acrylic monomer containing First, a copolymer containing a hydroxyl group-containing acrylic monomer, N-substituted maleimide, and another copolymerizable acrylyl monomer may be used. These other acrylic monomers include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, and the like. (Meth) acrylic acid esters, 2,2,2-Trifluoroethyl (meth) acrylate, 2,2,3,3,3,3-Pentyl fluorinated pill (meta) acrylate, 21- (perfluorinated) Unsaturated amines such as fluorinated (meth) acrylates such as hexyl) ethyl (meth) acrylate, (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, etc. And the like. Of these, (meth) acrylates are preferred from the viewpoint of increasing the yield of the copolymer. These other acrylic monomers may be used alone or in combination of two or more.

 When the above other acrylic monomer is contained, the ratio is preferably 1 to 80 mol%, and if it is more than 80 mol%, other components are relatively reduced, so that the effect of the present invention can be sufficiently obtained. It becomes difficult. These other acrylyl monomers can be introduced for the purpose of adjusting the solubility and hydrophobicity of the acrylic-soluble resin and controlling the molecular weight.

 Examples of the most preferable ratios of the respective monomers constituting the resin-soluble resin copolymer are 5 to 20 mol% of acryloxyl monomer having a hydroxyl group, 20 to 30 mol% of an acrylic monomer having a hydroxyl group, N-substituted maleimide is 20 to 40 mol%, and other acrylyl monomers are 10 to 55 mol%.

 The method for obtaining the soluble resin copolymer is not particularly limited. Generally, it is produced by radical polymerization of the above-mentioned monomers in a polymerization solvent. If necessary, these may be polymerized while protecting the functional groups of the monomers, and then subjected to a deprotection treatment.

Polymerization solvent used for producing alkali-soluble resin copolymer Examples include alcohols such as methanol, ethanol, propanol and butanol; ethers such as tetrahydrofuran and dioxane; aromatic hydrocarbons such as benzene, toluene and xylene; N, N-dimethylformamide; Polar solvents such as —methyl-2-pyrrolidone; esters such as ethyl acetate, butyl acetate and ethyl lactate; methyl 3-methoxypropionate; methyl 2-methoxypropionate; ethyl 3-methoxypropionate; Alkoxy esters such as ethyl methoxypropionate, ethyl 3-ethoxypropionate, and ethyl 2-ethoxypropionate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ester (Di) glycol dialkyl esters such as ethylene glycol, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol (Di) glycol monoalkyl ethers, such as methyl monomethyl ether, propylene glycol monoethyl ether, dipropylene dalicol monomethyl ether, dipropylene dalicol monoethyl ether, propylene glycol monomethyl ether acetate, carbitol acetate Glycol monoalkyl ether esters such as ethanol and ethyl acetate sorbacetate, cyclohexa Examples thereof include ketones such as nonone, methylethyl ketone, methyl isobutyl ketone, and 2-heptanone. These polymerization solvents can be used alone or in combination of two or more.

The molecular weight of the alkali-soluble resin copolymer contained in the positive photosensitive resin composition of the present invention is 1,000 to 200,000, preferably 2,0, in terms of polystyrene equivalent number average molecular weight. It is preferably from 000 to 500, 000, more preferably from 2,000 to 9,000. If the number average molecular weight is less than 1,000, the resulting pattern may have a poor shape, PC Monster 954

There is a tendency that the residual film ratio of the pattern decreases and the heat resistance of the pattern decreases. On the other hand, when the number average molecular weight exceeds 200,000, the applicability of the photosensitive resin composition becomes poor, the developability decreases, and the shape of the obtained pattern becomes poor. It may be bad. When the number average molecular weight exceeds 9,000, a residual film may exist between patterns of 50 / xm or less, and the resolution may be reduced. Therefore, when a fine pattern is formed, the number average molecular weight is preferably 9,000 or less, particularly preferably 8,000 or less.

<1, 2 monoquinonediazide compounds>

 The 1,2-quinonediazide compound contained in the positive photosensitive resin composition of the present invention is a compound having either a hydroxyl group or an amino group, or a compound having both a hydroxyl group and an amino group. A compound in which preferably 20 to 100%, particularly preferably 30 to 90% of the hydroxyl group and / or amino group of the above is esterified or amidated with 1,2-quinonediazidesulfonic acid can be used.

Examples of the compound having a hydroxyl group include phenol, o-cresol, m-cresol, p-cresol, octidoroquinone, resorcinol, catechol, 4,4-isopropylidenediphenyl / yl, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxyphenylsulfone, 4,4-hexafluoroisopropylidene diphenol, 4,4,4,4,1,1 Trihydroxytriphenylmethane, 1,1,1, tris (4-hydroxyphenyl) ethane, 4,4,1- [1- [4- [1- (4-hydroxyphenyl) -1-1-methylethyl] phenyl] Phenyl] ethylidene] bisphenol, 2,4-dihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 2,2,4,4,4-tetrahydroxybenzophenone, 2,3,4, Four, 1-tetrahydroxybenzophenone, 2,3,4,2,, 4 'pentahydroxybenzophenone, phenol compounds such as 2,5-bis (2-hydroxy-15-methylbenzylmethyl), ethanol, 2-propanol, Four Butanol, cyclohexanol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 2-methoxyethanol, 2-butoxyethanol, 2-methoxypropanol, 2-butoxypropanol, ethyl lactate, butyl lactate And aliphatic alcohols.

 Examples of the compound having an amino group include aniline, o-toluidine, m-toluidine, p-toluidine, 4-aminodiphenylmethane, 4-aminodiphenyl, o-phenylenediamine, and m-phenylenediamine. Examples thereof include anilines such as min, p-phenylenediamine, 4,4′-diaminodiphenylmethane, and 4,4′-diaminodiphenyl ether, and aminocyclohexane.

 Further, compounds having both a hydroxyl group and an amino group include, for example, o-aminophenol, m-aminophenol, p-aminophenol, 4-aminoresorcinol, 2,3-diaminophenol, 2, 4-diaminophenol, 4,4'diamino-4 '' '-hydroxytriphenylmethane, 4-amino-4', 4 ', dihydroxytriphenylmethane, bis (4-amino-3_hydroxypropyl-5-hydroxy Phenyl) ether, bis (4-amino-3-potassyl 5-hydroxyphenyl) methane, bis (4-amino-13-potoxy 5-hydroxyphenyl) sulfone, 2,2-bis (4-amino-phenyl) sulfone 3-caproloxy-5-hydroxyphenyl) propane, 2,2-bis (4-amino-13-carboxy-5-hydroxyphenyl) hexafluoropro Examples thereof include aminophenols such as bread, and alkanolamines such as 2-aminoethanol, 3-aminopropanol, and 4-aminocyclohexanol.

Among these 1,2-quinonediazide compounds, the balance of the development solubility difference between the exposed part and the unexposed part indicates that 4,4 '-[1-[4-[1- (4-hydroxyphenyl) 1-1] -Methylethyl] phenyl] ethylidene] 1,2-quinonediazidesulfonic acid ester of bisphenol is JP03 / 04954

 9 Preferred.

 The content of the 1,2-quinonediazide compound in the positive photosensitive resin composition of the present invention is preferably 5 to 100 parts by weight, more preferably 100 to 100 parts by weight, based on 100 parts by weight of the alkali-soluble resin component. Is from 10 to 50 parts by weight, most preferably from 10 to 30 parts by weight. If the amount of the 1,2-quinonediazide compound is less than 5 parts by weight based on 100 parts by weight of the alkali-soluble resin component, the solubility of the developer in the exposed part and the unexposed part of the positive photosensitive resin composition is reduced. When the difference is small, patterning by development may be difficult.On the other hand, when the amount exceeds 100 parts by weight, the 1,2-quinonediazide compound is not sufficiently decomposed by short-time exposure, and the sensitivity is reduced. Sometimes.

<Crosslinkable compound containing two or more epoxy groups>

The crosslinkable compound containing two or more epoxy groups contained in the positive photosensitive resin composition of the present invention is not particularly limited, but specific examples thereof include Evololi, an epoxy resin having a cyclohexenoxide structure. GT-401, GT-403, GT-301, GT-302, Celloxide 2021, Celloxide 300 (manufactured by Daicel Chemical Co., Ltd.), Bisphenol A Epoxy Co., Ltd. 100, 1, 102, 100, 103, 104, 100, 107, 109, 110, 82 8 (from Yuka Shell Epoxy Co., Ltd.), bisphenol F-type epoxy resin epicolate 807 (Yukaka Shell Epoxy Co., Ltd.), phenol nopolak epoxy resin 15 2, 154 (above, manufactured by Yuka Shell Epoxy), EPPN 201, 224 (The above products are manufactured by Nippon Kayaku Co., Ltd.), EOCN-102, EOCN-103S, EOCN-104S, EOCN-102, E〇CN_1 0 25, EOCN-1027 (from Nippon Kayaku Co., Ltd.), Epikote 180 S75 (from Yuka Shell Epoxy Co., Ltd.), Denacol EX_252, an alicyclic epoxy resin (Manufactured by Nagase Chemmutex Co., Ltd.), CY175, CY177, CY179 (above, manufactured by CI BA—GE I GY A.G), Araldite CY_182, CY-192, CY-184 (above, manufactured by CIBA-GEIGYA.G), Epiclone 200, Epiclon 400, (above, manufactured by Dainippon Ink Industries, Ltd.), Epikote 87 1, 872 (all, manufactured by Yuka Shell Epoxy Co., Ltd.), ED-5661, ED-5662 (all, manufactured by Seranes Coatings Co., Ltd.), aliphatic poly Glycidyl ether, Denacol EX-61-1, EX-61-2, EX-6-4, EX-62-2, EX-411, EX-5-12, EX-52 2, EX-421, EX-313, EX-314, EX-321 (manufactured by Nagase Chemmutex Co., Ltd.) and the like. These crosslinkable compounds can be used alone or in combination of two or more.

 Of these, epoxy resins having a cyclohexenoxide structure are preferred from the viewpoint of improving heat resistance and controlling the pattern shape by the crosslinking temperature.

 The content of the crosslinking compound containing two or more epoxy groups is preferably 1 to 50 parts by weight, more preferably 1 to 20 parts by weight, based on 100 parts by weight of the alkali-soluble resin component. Most preferred is 1 to 10 parts by weight. When the content of the epoxy group-containing crosslinkable compound is less than 1 part by weight, the crosslink density of the system becomes insufficient, so that heat resistance and solvent resistance after pattern formation are reduced, and when the amount exceeds 50 parts by weight. In this case, an uncrosslinked compound exists, and heat resistance and solvent resistance after pattern formation are reduced. When the content of the epoxy group-containing crosslinkable compound is large, the storage stability of the photosensitive resin composition may be deteriorated.

<Surfactant>

 The surfactant contained in the positive photosensitive resin composition of the present invention is a fluorine-based surfactant, a silicone-based surfactant, a nonionic surfactant, or the like, and is not particularly limited. From the height, a fluorine-based surfactant is preferred.

Specific examples of the fluorine-based surfactant include F-top EF301, EF303, EF355 (manufactured by Tochem Products), Megafac F 171, F173, R-30 (manufactured by Dainippon Ink Co., Ltd.), Florad FC 430, FC431 (manufactured by Sumitomo 3LM Co., Ltd.), Asahigard AG 710, sa One mouth S-380, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.) However, the present invention is not limited to these.

 The surfactant content in the positive photosensitive resin composition of the present invention is preferably 0.01 to 2 parts by weight, more preferably 0.02 parts by weight, based on 100 parts by weight of the alkali-soluble resin component. The amount is from 1 to 1 part by weight, most preferably from 0.101 to 0.1 part by weight. When the content of the surfactant is more than 2 parts by weight, the coating film tends to be uneven, and when the content is less than 0.01 parts by weight, striations and the like are easily generated in the coating film. To obtain a film thickness of 2.5 or more, it is preferable to add 0.04 to 1 part by weight.

 Examples of the most preferable content of each component contained in the positive-type photosensitive resin composition of the present invention are as follows: 100 parts by weight of the alkali-soluble resin component, and a 1,2-quinonediazide compound of 10 to 10 parts by weight. 30 parts by weight, 1 to 10 parts by weight of a crosslinkable compound containing two or more epoxy groups, and 0.01 to 0.1 parts by weight of a surfactant.

And other components that may be contained>

Needless to say, the positive photosensitive resin composition of the present invention preferably contains an adhesion promoter for the purpose of improving the adhesion to the substrate after development. Specific examples of such an adhesion promoter include chlorosilanes such as trimethylchlorosilane, dimethylvinylchlorosilane, methyldiphenylchlorosilane, chloromethyldimethylchlorosilane, trimethylmethoxysilane, dimethylmethoxysilane, methyldimethoxysilane, and the like. Alkoxysilanes such as dimethylvinylethoxysilane, diphenyldimethoxysilane, and phenyltriethoxysilane; hexamethyldisilazane; N, N'-bis (trimethylsilyl) perrea; dimethyltrimethylsilylamine; Silazanes such as trimethylsilylimidazole, vinyltrichlorosilane, archloropropyltrimethoxysilane, araminopropyl trier Silanes such as toxoxysilane, α-methacryloxypropyltrimethoxysilane, T-dalicidoxypropyltrimethoxysilane, benzotriazole, benzimidazole, indazole, imidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole Heterocyclic compounds such as 1,2-mercaptobenzozoxazole, perazole, thioperacyl, mercaptoimidazole, mercaptopyrimidine, and urea or thiourea compounds such as 1,1-dimethylperyl and 1,3-dimethylperyl. Can be.

 The use ratio of these adhesion promoters is usually 20 parts by weight or less, preferably 0.05 to 10 parts by weight, particularly preferably 1 to 1 part by weight with respect to 100 parts by weight of the alkali-soluble resin component. 0 parts by weight.

 The positive photosensitive resin composition of the present invention may further contain a pigment, a dye, a storage stabilizer, an antifoaming agent, and the like, if necessary.

<Positive photosensitive resin composition>

The positive photosensitive resin composition of the present invention can be easily prepared by uniformly mixing the above components, and is usually used in the form of a solution dissolved in an appropriate solvent. For example, an alkali-soluble resin is dissolved in a solvent, and a 1,2,2-quinonediazide compound, a crosslinkable compound containing two or more epoxy groups, a surfactant, and other components, if necessary, are added to the solution at a predetermined ratio. The photosensitive resin composition can be prepared as a solution by mixing. Examples of such a solvent include ethylene glycol monomethyl ether, ethylene dalicol monoethyl ether, methyl cetyl sorb acetate, ethyl sesole sorb acetate, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether, and propylene. Glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, 2 —Hydroxy-2-methylethyl propionate, ethoxy vinegar 03 04954

 13 Ethyl acid, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, pyruvate Ethyl acid, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate and the like can be used. These organic solvents are used alone or in combination of two or more.

 Further, a high boiling point solvent such as propylene glycol monobutyl ether and propylene glycol monobutyl ether acetate can be mixed and used. Among these solvents, propylene dalicol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, and cyclohexanone are preferred for improving the leveling property.

 The solid content concentration when the positive photosensitive resin composition of the present invention is made into a solution is not particularly limited as long as each component is uniformly dissolved. Usually, it is generally used preferably in the range of 1 to 50% by weight, particularly preferably in the range of 20 to 45% by weight, from the viewpoint of easiness of the processed surface. The viscosity of the solution is preferably from 5 to 60 mPa * s, particularly preferably from 10 to 40 mPa * s. Further, the positive photosensitive resin composition solution prepared as described above is preferably used after being filtered using a filter having a pore diameter of about 0.5 m or the like. The solution of the positive photosensitive resin composition thus prepared is excellent in long-term storage stability at room temperature.

 The solution of the positive-type photosensitive resin composition of the present invention is applied on a substrate such as a glass substrate, a silicone wafer, an oxide film, or a nitride film, and then applied at 80 to 130 for 30 seconds to 600. The coating film can be formed by pre-drying for 2 seconds.

By mounting a mask having a predetermined pattern on the coating film, irradiating light and developing with an alkali developing solution, the exposed portion is washed out and a sharp relief pattern of an end face is obtained. The developer used at this time may be any alkaline aqueous solution, such as an alkali metal hydroxide such as potassium hydroxide, sodium hydroxide, potassium carbonate or sodium carbonate. 03 04954

 Examples thereof include aqueous solutions of hydrides, aqueous solutions of quaternary ammonium hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline, and aqueous amine solutions such as ethanolamine, propylamine, and ethylenediamine.

 The alkaline developer is generally an aqueous solution of 10% by weight or less, preferably a 0.5 to 3.0% by weight aqueous solution. The photosensitive resin composition of the present invention can be developed with a 2.38% by weight aqueous solution of tetraethylammonium hydroxide generally used for a photoresist without swelling or the like. Further, an alcohol or a surfactant may be added to the above-mentioned developer for use. Each of these is blended preferably in a range of 0.05 to 10 parts by weight with respect to 100 parts by weight of the developer.

 The development time is usually 15 to 180 seconds. Further, the developing method may be any of a puddle method, a dive method and the like. After the development, washing with running water is performed for 20 to 90 seconds, and the substrate is air-dried with compressed air or compressed nitrogen to remove moisture on the substrate and form a patterned coating film. Thereafter, the entire surface of the patterned coating film is irradiated with light from a high-pressure mercury lamp or the like to completely decompose the 1,2-quinonediazide compound remaining in the patterned coating film. Subsequently, the coating film is heat-resistant, transparent, flattened, has low water absorption, chemical resistance, and has a good relief pattern by performing a bot bake using a hot plate or oven. Can be obtained. The postbaking may be performed, for example, at a temperature of 140 to 250 ° C, for 5 to 30 minutes on a hot plate, and for 30 to 90 minutes in an oven.

How to Obtain a Pattern Shape with an Arbitrary Semicircular or Trapezoidal Cross Section>

 The positive photosensitive resin composition of the present invention can obtain a pattern shape having an arbitrary semicircular or trapezoidal cross section by changing the conditions of the bost bake.

In order to obtain a pattern with a semicircular cross-section, a single-stage boost bake at a relatively high temperature may be performed. The temperature is from 170 to 250, preferably from 190 to 220 ° C. 4954

 15 On the other hand, in order to obtain a pattern with a trapezoidal cross section, it is necessary to perform a two-stage bost bake in which heating is performed at a relatively low temperature for 10 to 30 minutes and then at a relatively high temperature. The first-stage temperature is 120 to 160 ° C, preferably 130 to 150 ° C, and the second-stage temperature is 170 to 250 ° C, preferably 190-250 ° C.

 Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

 <Example 1>

 [Each component of the composition]

 Alkali-soluble resin: 13.5 mol% of methacrylic acid, 35.3 mol% of N-cyclohexylmaleimide, 25.5 mol% of hydroxymethyl methacrylate and 25.7 mol% of methyl methacrylate as monomers Copolymer (number average molecular weight 4100 (in terms of polystyrene))

 1,2-quinonediazide compound: 4,4 '_ [1- [4- [1- (4-hydroxyphenyl) -1-1-methylethyl] phenyl] ethylidene] bisphenol 1 mo 1 and 1,2-naphthoquinone-1 2 —A photosensitizer synthesized by a condensation reaction with diazido 5-sulfonyl chloride 2mo1 (Toyo Gosei Co., Ltd., P—200)

 Crosslinkable compound containing two or more epoxy groups: GT-401 with tetrafunctional cyclohexenoxide structure (manufactured by Daicel Chemical Industries, Ltd.) Surfactant: Fluorine-based Megafac R-30 (Large) Nippon Ink Kagakusha)

 [Preparation of positive photosensitive resin composition]

Dissolve 22 g of Alkyli-soluble resin in 78 g of propylene dalicol monomethyl ether acetate, and add 6.6 g of 1,2-quinonediazide compound to a crosslinkable resin containing two or more epoxy groups. After adding 1 g of the compound, 0.01 g of the surfactant, and 1 g of α-methylacryloxypropyltrimethoxysilane as an adhesion aid, the mixture was stirred at room temperature for 1 hour to obtain the positive photosensitive material of the present invention. A composition solution (1) as a resin composition was prepared. The viscosity of the composition solution (1) was 13.9 mPa · s, and no change was observed in the viscosity even after being left at room temperature for 3 months.

 [Evaluation of water absorption of cured film]

The composition solution (1) was applied to a glass substrate with silicon oxide using an overnight spin coater, and then prebaked on a hot plate at 120 ° C for 90 seconds to obtain a film thickness of 1.7 Was formed. The entire surface of the obtained coating film was irradiated with ultraviolet light having a light intensity of 9 mWZ cm ² at 420 nm for 30 seconds (270 mJ / cm ² ). The coating film after UV irradiation was post-baked by heating at 20 Ot for 15 minutes to form a cured film having a thickness of 1.5 / im. When the cured film thus formed was observed with an optical microscope, no abnormality such as occurrence of striation was observed.

 The water absorption of this cured film left at 23 ° C and 50% humidity of 50% for 24 hours, and the water absorption after boiling for 2 hours was measured using a thermogravimetric analyzer (TG-DTA, manufactured by Mac Science) at 120 ° C. The water absorption at 23 ° C and 50% humidity for 24 hours was 1.6%, and the water absorption for boiling for 2 hours was 1.7%.

 [Evaluation of heat resistance of cured film]

 The cured film produced in the same manner as above was scraped from the substrate, and the heat resistance was evaluated by TG-DTA measurement. As a result, the thermal decomposition onset temperature was 270 ° C, and the 5% weight loss temperature was 330 ° C. The glass transition temperature was 200 ° C. or higher.

 [Evaluation of transparency of cured film]

 A cured film was obtained in the same manner as described above, using a quartz substrate instead of the glass substrate with silicon oxide. The cured film was measured at a wavelength of 200 to 800 nm using a spectrophotometer, and the transmittance at 400 nm was 96%.

 [Evaluation of photosensitive characteristics]

The composition solution (1) was applied on a glass substrate with silicon oxide using a spin coater, and then prebaked on a hot plate at 120 for 90 seconds to obtain a coating with a film thickness of 1.7 / xm. A film was formed. Through a test mask on this coating Ultraviolet irradiation apparatus (manufactured by Canon Inc., P LA- 5 0 1), the light intensity at 42 0 nm 1 0 seconds UV ^{9mWZc m 2 (9 0m J /} cm 2) was irradiated. Next, it was immersed in a 2.38% TMAH aqueous solution (manufactured by Tokyo Ohka Co., Ltd., NMD-3) at 23 ° C for 45 seconds, developed, and washed with running ultrapure water for 20 seconds. A positive pattern was formed.

The film thickness of the unexposed part of the developing layer was about 1.Ί zm, and no film reduction was observed at all. The pattern resolution was up to 3 zm in line / space without pattern peeling. Thereafter, the entire surface 3 0 seconds light intensity ultraviolet radiation 9MWZc m ² at 42 0 nm (2 7 0 m J / cm 2) was irradiated, to post-bake of 2 0 0 1 5 minutes, the film thickness A pattern of 1.5 zm was obtained. When the cross-sectional shape of this pattern was evaluated using a scanning electron microscope, it was a semicircular pattern as shown in FIG.

 [Evaluation of sensitivity]

In the above pattern formation, by changing the amount of irradiation before development ultraviolet by 1 Om JZ cm ² with ultraviolet irradiation treatment, an exposure unit measures the minimum amount of UV irradiation needed to completely dissolve in the developer However, it was completely dissolved by irradiation with 5 OmJ Zcm ² .

 <Example 2>

 In the evaluation of the photosensitive characteristics of Example 1, the temperature was changed to a one-stage boost bake at 200 ° C. for 15 minutes, heated at 140 ° C. for 15 minutes on a hot plate, and then heated at 200 ° C. for 15 minutes. A two-stage postbake of heating for a minute was performed. As a result, the cross-sectional shape of the obtained pattern was a trapezoidal pattern as shown in FIG.

 <Example 3>

As an alkali-soluble resin, it consists of 9% by mole of methacrylic acid, 32.8% by mole of N-cyclohexylmaleimide, 25.4% by mole of hydroxyethyl methacrylate and 32.8% by mole of methyl methacrylate. Except for using a copolymer (number average molecular weight of 3900 (in terms of polystyrene)), the same preparation as in Example 1 was carried out, and a composition solution (2) which was a positive photosensitive resin composition of the present invention was prepared. I got The viscosity of the composition solution (2) is 1 3. OmPa · s, No change in viscosity was observed even after 3 months at room temperature.

 Evaluation was performed in the same manner as in Example 1 using this composition solution (2). As a result, no abnormality such as striation was observed in the cured film, the transmittance at 400 nm was 96%, the 5% weight loss temperature was 330 ° C, and the glass transition temperature was 200 ° C or more. Met.

In the evaluation of the photosensitive characteristics, no film loss was observed in the unexposed areas after development, the pattern resolution was formed up to 3 m in the line Z space without pattern peeling, and the cross-sectional shape of the pattern was semicircular. Was. Sensitivity was measured at 50 mJ / cm ² .

 <Example 4>

 A composition solution (3) as a positive photosensitive composition of the present invention was obtained in the same manner as in Example 1 except that cyclohexanone was used instead of propylene glycol monomethyl ether acetate as a solvent. The viscosity of the composition solution (3) was 13.9 mPa · s, and no change was observed in the viscosity even after standing at room temperature for 3 months.

 Evaluation was performed in the same manner as in Example 1 using this composition solution (3). As a result, no abnormality such as striation was observed in the cured film, the transmittance at 400 nm was 96%, the 5% weight loss temperature was 330 ° C, and the glass transition temperature was 200 or more. there were.

In the evaluation of the photosensitive characteristics, no film loss was observed in the unexposed areas after development, and the pattern resolution was 3 lines / space without pattern peeling, and the cross-sectional shape of the pattern was semicircular. . Sensitivity was 50 mJZ cm ² .

 <Comparative Example 1>

As an alkali-soluble resin, a copolymer (number-average molecular weight: 4100 (polystyrene equivalent)) composed of 13.5 mol% of methacrylic acid, 25.5 mol% of hydroxyethyl methacrylate and 61 mol% of methyl methacrylate was used. A composition solution (4) was obtained in the same manner as in Example 1 except that the composition was used. Evaluation was performed in the same manner as in Example 1 using this composition solution (4). As a result, no abnormality such as generation of striation was observed in the cured film, and the transmittance at 400 nm was 96%, but the 5% weight loss temperature was 290 and the heat resistance was high. It was inferior in sex.

In the evaluation of the photosensitive characteristics, no film reduction was observed in the unexposed areas after development, and the pattern resolution was formed without pattern peeling up to 3 im in the line Z space, and the pattern cross-section was semicircular. Was. Sensitivity was found to be 50m J / cm ^2.

 <Comparative Example 2>

 In Comparative Example 1, a single-stage postbake for 15 minutes at 200 ° C. was performed in the same manner as in Example 2, and heated on a hot plate at 140 ° C. for 15 minutes. The substrate was heated for 15 minutes and subjected to a two-stage bake bake. However, the cross-sectional shape of the obtained pattern was semicircular, and a trapezoidal pattern as shown in FIG. 2 was not obtained.

 <Example 5>

 A composition solution (5) was obtained in the same manner as in Example 1 except that the alkali-soluble resin having a number-average molecular weight of 10,000 was used.

 Evaluation was performed in the same manner as in Example 1 using this composition solution (5). As a result, no abnormality such as generation of striation was observed in the cured film, the transmittance at 400 nm was 96%, the 5% weight loss temperature was 330 ° C, and the glass transition temperature was The temperature was 200 ° C. or higher.

 In the evaluation of the photosensitive characteristics, no film loss was observed in the unexposed areas after development, but there was a residual film after development between patterns of 50 m or less in line / space. This phenomenon was not resolved. The cross section of the pattern was semicircular.

 <Comparative Example 3>

A composition solution (6) was obtained in Example 1 without adding a surfactant. Evaluation was performed in the same manner as in Example 1 using this composition solution (6). So As a result, striation occurred in the cured film, and a normal film could not be obtained. Industrial applicability

 The positive-type photosensitive resin composition of the present invention has high-sensitivity, high-resolution positive-type photosensitive characteristics, is easily etched with an alkaline aqueous solution, and can be exposed using a mask having a predetermined pattern. Thereby, a coating film having a relief pattern with a fine shape and high dimensional accuracy can be easily obtained.

 Further, the positive photosensitive resin composition of the present invention has high sensitivity and can be developed using a commonly used aqueous solution of 2.38% by weight of tetramethylammonium hydroxide. In addition, an arbitrary pattern shape having a semicircular or trapezoidal cross section can be formed depending on postbaking conditions. Further, a pattern having excellent properties such as transparency, heat resistance, flattening property, and low water absorption can be easily formed by a curing treatment after the pattern formation. The positive photosensitive resin composition of the present invention can be used as an interlayer insulating film of a TFT used for an LCD, protection of a color filter, a flattening film, an uneven film under an A1 film used as a reflecting plate of a reflective display, It is suitable as a lens material, a material for forming an insulating film of an organic EL element, and the like.

Claims

W0 03/087941 PC leak 3/04954 21 Claims

1. A composition containing an alkali-soluble resin, a 1,2-quinonediazide compound, a crosslinkable compound containing two or more epoxy groups, and a surfactant, wherein the alkali-soluble resin is A positive photosensitive resin composition characterized by being a copolymer containing, as essential components, an acryloxyl group-containing acryl monomer, a hydroxyl group-containing acrylic monomer and an N-substituted maleimide.

 2. With respect to 100 parts by weight of the alkali-soluble resin component, 5 to 100 parts by weight of 1,2-quinonediazide and 1 to 50 parts by weight of a crosslinkable compound containing two or more epoxy groups. The positive photosensitive resin composition according to claim 1, wherein the positive photosensitive resin composition contains 0.01 to 2 parts by weight of a surfactant.

 3. The positive photosensitive resin composition according to claim 1 or 2, wherein the copolymer has a number average molecular weight of 2,000 to 9,000.

 4. The copolymer contains 5 to 30 mol% of a propyloxyl group-containing acrylic monomer, 5 to 50 mol% of a hydroxyl group-containing acrylic monomer, and 10 to 70 mol% of an N-substituted maleimide. Item 3. The positive photosensitive resin composition according to item 1 or 2.

 5. The positive photosensitive resin composition according to claim 1, wherein the surfactant is a fluorine-based surfactant.

 6. A pattern shape having a semicircular or trapezoidal arbitrary cross section is obtained by using the positive photosensitive resin composition according to any one of claims 1 to 5 and changing post bake conditions. Pattern forming method.